WASHINGTON, Aug 4 (Reuters) - Hurricane Ivan, which caused a swathe of destruction across the Caribbean last September before crashing into the U.S. Gulf coast, generated ocean waves more than 90 feet (27 metres) high, researchers said on Thursday.

They may have been the tallest waves ever measured with modern instruments, suggesting that prior estimates for maximum hurricane wave heights are too low, William Teague of the Naval Research Laboratory at the Stennis Space Center in Mississippi and colleagues reported.